In Wilbur’s math class his grade is based on the average score of six tests, each worth 100 points. Wilbur worries about his grade. He knows that his average on the first four tests is 88.5. What is the lowest average he can get on his next two tests and still average 90 overall?
* Personally I don't think there's enough information to figure this out*
Good Luck
2007-02-27 14:07:43 · 11 answers · asked by Shorty 3 in Education & Reference ➔ Homework Help
there are several ways to answer, but if you add 1.5 to 88.5 to make it 90 then you have added 4X1.5 or six points so you need to get 93 on the next 2 tests. I don't have a formal education. so the teacher may not like this. Remember there are many ways to do a job right.
2007-02-27 14:23:51 · answer #1 · answered by jekin 5 · 0⤊ 1⤋
90 X 6 = 540, therefore the total for all 6 tests combined must equal 540.
Since after4 tests his average is 88.5, the total for those 4 tests is 88.5 X 4, which equals 354.
When you subtract, 540 - 354 = 186.
Therefore in sum of the final 2 tests must be at least 186 points. If he were to get the same score on each test, he would need a 93 on each test. He could also, however, get a 100 on one test and an 86 on the other.
As long as the last two test add up to 186, he will have his average.
Good luck.
2007-02-27 14:22:24 · answer #2 · answered by David H 2 · 0⤊ 0⤋
ok...in order to get a 90...he would need to earn 90*6=540 points. If 4 tests averaged 88.5, then he earned 4*88.5=354 points. Therefore, on the last 2 tests he would need to earn 540-354=186 points...so 93 average on both tests...
2007-02-27 14:31:37 · answer #3 · answered by k t 4 · 0⤊ 0⤋
first I would multiply 88.5 by 4 to find the total score of the first 4 tests
=354
then multiply 90 by 6 to find the desired total for all 6 testd
=540
subtract each from 600 sepertaly
=246
=60
subtract these two numbers
=186
divide by 2
=93 is the lowest average he can get on the next two test
2007-02-27 14:20:52 · answer #4 · answered by sarahanne_2001 2 · 0⤊ 0⤋
90% overall
6 x 100 = 600 total points available
90% x 600 - 540 points needed for 90% average overall
88.5 x 4 = 354 current points
540 - 354 = 186 points need for 90%
186/2 = 93
He needs to average 93% on his next 2 tests to get a 90% overall
2007-02-27 14:20:30 · answer #5 · answered by debwils_4kids 4 · 0⤊ 0⤋
4(88.5) = 354 points so far.
if x is the average for his next two tests the total for those two would be 2x
90% of the 600 total points would be .90(600)
(354 + 2x) is the total for all six of his tests.
Set those equal and solve.
354 + 2x = .90(600)
354 + 2x = 540
2x = 186
x = 93 is the average needed on the next two test.
2007-02-27 14:27:39 · answer #6 · answered by PZ 4 · 0⤊ 0⤋
so basically, Wilbur has a total of six tests. The first four on average is 88.5. He need two tests to raise his average to 90. so, it would be (88.5+x)/2=90. You're finding the average of two averages. multiply by both sides to get 88.5+x=180. subtract 88.5 on both sides to get x=91.5
so, he needs an average of 91.5% to get 90% overall
2007-02-27 14:18:46 · answer #7 · answered by asiduhagu 3 · 0⤊ 1⤋
He would need 540 pts. overall to get a 90%. On the first four tests, he got 354 pts., so he needs to get 186 pts. on the next two tests. 186/2= 93% He must average no lower than 93% on the last two tests.
2007-02-27 14:16:20 · answer #8 · answered by zoogrl2001 3 · 0⤊ 0⤋
I was supposed to be first.
The answer is
93
6*9 = 540-354=186/2=93
2007-02-27 15:18:32 · answer #9 · answered by professorc 7 · 0⤊ 0⤋
He would need to get 95 on his next 2 tests
2007-02-27 14:17:40 · answer #10 · answered by dipper8550 3 · 0⤊ 1⤋